I am isolating polyA+ RNA from the heads of a tiny insect that, like
Drosophila, has red eyes.
An intense red coloration (I suppose from the eyes) remains both in
total RNA and polyA+ RNA.
With the polyA+ RNA I succesfully did RT-PCR reactions, so I did not
worry much(however I do not know whether they would improve not having
the red pigment around).
I worry now that I possibly will use the polyA+ RNA for constructing a
cDNA library.

I used RNeasy Kit for total RNA isolation and an Ambion kit for the
polyA+ RNA purification. With following results:
total RNA:
A260/280: >1.9
A260/230: approx. 1.0
polyA+ RNA:
A260/280: approx. 1.8
A260/230: approx. 0.8
(Gel: no degradation)